Neutrinos in Non-linear Structure Formation - a Simple SPH Approach

Abstract

We present a novel method for implementing massive neutrinos in N-body simulations. Instead of sampling the neutrino velocity distribution by individual point particles we take neutrino free-streaming into account by treating it as an effective redshift dependent sound speed in a perfect isothermal fluid, and assume a relation between the sound speed and velocity dispersion of the neutrinos. Although the method fails to accurately model the true neutrino power spectrum, it is able to calculate the total matter power spectrum to the same accuracy as more complex hybrid neutrino methods, except on very small scales. We also present an easy way to update the publicly available Gadget-2 version with this neutrino approximation.

13 pages, 7 figures

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Cited by in corpus (16)

• Euclid preparation: IX. EuclidEmulator2 -- Power spectrum emulation with massive neutrinos and self-consistent dark energy perturbations
• An efficient implementation of massive neutrinos in non-linear structure formation simulations
• Structure formation with massive neutrinos: going beyond linear theory
• An Efficient and Accurate Hybrid Method for Simulating Non-Linear Neutrino Structure
• An optimal nonlinear method for simulating relic neutrinos
• Scale-dependent bias and bispectrum in neutrino separate universe simulations
• Constraints on neutrino masses from Planck and Galaxy Clustering data
• COLA with massive neutrinos
• First detection of scale-dependent linear halo bias in $N$-body simulations with massive neutrinos
• Higher-order massive neutrino perturbations in large-scale structure
• Describing massive neutrinos in cosmology as a collection of independent flows
• Massive neutrinos and degeneracies in Lyman-alpha forest simulations
• Geodesic motion and phase-space evolution of massive neutrinos
• Cosmological Perturbation Theory for streams of relativistic particles
• Probing Neutrinos from Planck and Forthcoming Galaxy Redshift Surveys
• Measuring neutrino mass and asymmetry with matter pairwise velocities